Here are a few notes and observations from Sunday's Detroit Lions training camp practice.

• Running back Steven Miller, an undrafted free agent out of Appalachian State, has been flashing while running with the third team. His change-of-direction quickness has always been apparent, and it's translating to team drills.

Miller twice bounced runs outside during the team's first padded practice, getting to the edge untouched. He's also been active as a pass-catcher, providing quarterbacks Kellen Moore and Thaddeus Lewis with an outlet on swing routes.

Miller has an uphill battle to earn a roster spot, with five other running backs starting ahead of him on the depth chart, but if he makes some plays in the preseason, particularly as a return man, he could work his way into the discussion.

• Cornerback Bill Bentley continued his strong start to training camp, breaking up several more passes. He's playing with extraordinary confidence after missing the majority of his rookie season with a shoulder injury. He could provide the Lions with a huge boost as a playmaking nickelback.

• There was some fierce competition in one-on-one drills between the offensive and defensive linemen today. Second-year offensive tackle Riley Reiff looks outstanding and appears to be carrying the weight he added in the offseason well.

• First-team reps at key position battles went to Tahir Whitehead at outside linebacker, Darius Slay at cornerback, Corey Hilliard at right tackle and Dylan Gandy at right guard. Rookie Larry Warford, who some thought might be in line for a day with the first team, worked with the second unit.

• Early in practice Calvin Johnson blew past cornerback Jonte Green on a deep route. Quarterback Matthew Stafford threw a perfect pass, hitting Johnson in stride 45 yards down the field, but the star receiver couldn't hang on for the touchdown. A rare mistake for Megatron, who was visibly frustrated with himself.

Johnson made up for the mistake later, making an extremely difficult reception deep down the right sideline with both Chris Houston and Glover Quin in tight coverage. The newly acquired safety appeared to have a hand in between Johnson's arms, but it wasn't enough to stop the receiver from overpowering the defensive backs.

• A scary moment in practice today when linebacker Alex Elkins came around the outside edge and blocked a punt off the foot of Blake Clingan. Elkins was unable to slow his momentum, plowing through Clingan, taking the punter awkwardly to the ground. Despite being shaken up on the play, Clingan returned to practice, and in the locker room after the session, told me he felt fine.

Had the play occurred in a game, it would have been a clean block. Elkins clearly got a hand on the ball before running into Clingan.

• Rookie receiver Corey Fuller got a crack at punt return today, joining a long list of candidates for that role. Unfortunately, he muffed the only attempt I watched him handle.

• Defensive end Ezekiel Ansah continues to have an up-and-down first couple of days of camp. He's especially had a problem jumping offside on hard counts, but then there are the plays where he displays his rare athleticism to remind you of his potential.

On Sunday, Ansah quickly abandoned his pass rush when he identified a screen pass. He was able to drop back in coverage, shadow speedy running back Theo Riddick and stop the play for what would have been just a short gain.

• It's early, and who knows what we'll see once we get to the preseason games, but the Lions cornerbacks have been playing far more aggressively with their coverages through the first few practices.

The team is still running a fair share of off-man and zone looks, but there's certainly a greater of percentage of plays where the CBs are up on the line of scrimmage, jamming receivers off the ball. It makes sense given Detroit has bolstered their depth at safety and continued to add size to the secondary.